Gusto, formerly known as ZenPayroll, announced on Tuesday that it serves 40,000 small businesses, double Zenefits' last publicized customer count. Gusto also unveiled its own new human resources features for employee records, onboarding, and employee savings--adding to existing payroll and benefits functions.

“We know HR people wear many hats, and until today, they’ve had to log in to multiple systems to manage compliance rules, process paperwork, and access employee information,” Gusto CEO Josh Reeves said in a statement. “Gusto gives them one home for HR, payroll and benefits so they can spend more time welcoming new teammates and empowering them.”

Unlike Zenefits, which ballooned to about 1400 employees before layoffs earlier this year, Gusto has stayed relatively lean while pursuing this vision. It has raised just over $150 million to date. Reeves told reporters at a product briefing that he expects to employ 350 people by the end of the year between San Francisco and Denver.

Reeves doesn't hesitate to compare the two startups, saying he has been "thrilled" by the number of customers they've won from Zenefits, many of whom have "horror stories" about dealing with their competitor. "We're also excited to have our valuation double from the last round, compared with other companies that have had their valuations cut in half," he said.

Gusto's new features go a step further than the startup's roots in payroll processing and insurance benefits, which the company introduced earlier this year. It wants to eventually handle all of a small businesses' critical HR tasks online, from hiring new employees to offering 401(k) plans to creating individualized savings plans that distribute money directly from your paycheck.

The product rollout comes just weeks before Zenefits is expected to announce its own set of new product features at its Z2 conference in San Francisco. "Z2 sounds like a sequel, but ideally the first movie would stand on its own," Reeves quipped.

Brian Solomon was a Forbes staff writer from 2011 to 2017 covering technology, entrepreneurs, billionaires, and more. Follow him on Twitter, Facebook and LinkedIn.